Malaria, TB and HIV-1 remain tremendous disease burdens in much of the world's population. Despite decades of effort, there are no vaccines for malaria or HIV-1. Sub-Saharan populations are those that will benefit most from vaccines for malaria, TB and HIV-1. The majority of individuals in sub-Saharan countries, with prevalence exceeding 90% in many areas of Africa, are infected with one or more species of parasitic helminths that suppress immune responses, skew the host immune system of human and animals to T-helper type 2 (Th2), and suppress vaccine-specific responses. Therefore, there is a potential that helminth infected populations may not generate the desired immune responses to vaccines designed to drive Th1-type and cytotoxic T-cell responses. Previous work has shown that a naked DNA vaccine for HIV-1 was unable to generate antigen-specific T cell mediated immune responses unless helminth infection was eliminated prior to vaccination (Da'dara et al., Vaccine. 2010 Feb. 3; 28(5):1310-7. Epub 2009 Nov. 24, incorporated herein by reference in its entirety).
It is clearly important to HIV and other prevalent infectious diseases vaccine development for the developing world, to find a vaccine that will drive significant vaccine-specific Th1 immune responses in parasitically infected recipients.